Method and kit for testing polyolester lubricants used in refrigerant compressors

A method for testing the fitness of a polyolester lubricant for use in a refrigerant compressor, said lubricant being prepared by the reaction of trimethylopropane with branched and linear acids to create a polyolester lubricant having acidic groups which are attached to the resulting polyolester, having a maximum acceptable total acid number (TAN) of 0.60, comprising the steps of:

• a) obtaining a polyolester lubricant sample to be tested;
• b) preparing a solution for indicating a total acid number in said polyolester lubricant of over 0.60 by mixing 9.7 milliliters of a 0.01% solution of alizarin in methanol with 0.3 milliliters of 10N KOH in methanol to create a color changing acidity indicator with a sufficient amount of alkaline to neutralize said maximum acceptable total acid number of 0.60 of said lubricant so that said indicating solution indicates an excess acidity condition of the polyolester lubricant by changing color only upon contact with said lubricant having a total acid number of 0.6 or greater;
• c) mixing said indicating solution with a 5 milliliters of lubricant sample to produce a reaction mixture;
• d) observing the color of the reaction mixture;
• and
• e) determining the total acid number of 0.6 or greater if the indicating solution changes color and a total acid number of less than 0.6 if no color change occurs upon contact of the indicating solution with the lubricant in the reaction mixture, wherein a change in color indicates an excess acidity condition of the polyolester lubricant indicating that said lubricant is unfit for further service and wherein no color change is an indication of an acceptable acidity condition of the lubricant such that said polyolester lubricant is fit for use in the refrigerant compressor.